body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: #f4f6f8;
    color: #333;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
}

.container {
    background-color: #fff;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    text-align: center;
    width: 90%;
    max-width: 600px;
}

h1 {
    margin-bottom: 1.5rem;
    font-size: 1.8rem;
    color: #111;
}

.upload-area {
    margin-bottom: 1.5rem;
}

#drop-zone {
    border: 2px dashed #ccc;
    border-radius: 8px;
    padding: 2rem;
    cursor: pointer;
    transition: border-color 0.3s, background-color 0.3s;
}

#drop-zone.dragover {
    border-color: #007bff;
    background-color: #f0f8ff;
}

#drop-zone p {
    margin: 0 0 1rem;
    font-size: 1.1rem;
}

#browse-btn {
    background-color: #007bff;
    color: #fff;
    border: none;
    padding: 0.8rem 1.5rem;
    border-radius: 5px;
    font-size: 1rem;
    cursor: pointer;
    transition: background-color 0.3s;
}

#browse-btn:hover {
    background-color: #0056b3;
}

#message-area {
    margin-top: 1rem;
    font-size: 1rem;
}

#download-area a {
    display: inline-block;
    margin-top: 1rem;
    background-color: #28a745;
    color: #fff;
    padding: 0.8rem 1.5rem;
    border-radius: 5px;
    text-decoration: none;
    font-size: 1rem;
    transition: background-color 0.3s;
}

#download-area a:hover {
    background-color: #218838;
}

.error {
    color: #dc3545;
}

.success {
    color: #28a745;
}
